Black Swift board has 2 integrated Ethernet (10/100 Mbps) ports, but to use them you need to add a few external components. There are two ways to use them:

  • Regular RJ-45 socket and transformer
  • Transformerless design

Regular RJ-45 socket

Ethernet requires galvanic isolation between devices, and to provide it you have to use specialiazed transformer. Simplest way here is to use RJ-45 socket with integrated transformer (e.g. HR911105A from Hanrun Electronics, easily available on eBay):

Transformerless design

In case you need short Ethernet connection between two modules within same device or even same mainboard, usually there's no need in galvanic isolation so you can omit transformers:

NB: transformerless design is not, repeat NOT, suitable for long-distance inter-device communication, and may damage your device(s) due to difference in ground levels and/or induced voltages!